This application claims the benefit of Korean Patent Application No. 1998-44375, filed on Oct. 22, 1998, which is hereby incorporated by reference.
1. Field of the Invention
The present invention relates to a liquid crystal display device, more particularly, to a glass substrate for liquid crystal display device.
2. Discussion of the Related Art
Although portable televisions and notebook computers having liquid crystal displays (LCDs) have been in the market, there are various problems to be solved yet. Because these televisions and computers have portable electronics, the reduction of the size and weight is very important in the LCD research.
Recently, a study for small size and light weight portable television and notebook computer has been conducted deeply in order to increase the portability of these products.
There are various methods to reduce the size and weight of the LCD. It is difficult to reduce the number of the necessary elements of the LCD. In addition, the weight and size of the necessary elements are so small already that the weight and size of the necessary elements can hardly be reduced. For the glass substrate which is a basic element of the LCD, there is the possibility of weight reduction. In particular, the weight reduction of the glass substrate is a very important technique because of its large portion of total weight of the LCD.
To reduce the weight of the glass substrate means to make the substrate thinner. The glass processing technique is a very difficult technique, however, because the processed thin glass is easily damaged and its surface becomes rough.
The most useful method for weight reduction of the glass substrate is to etch the surface of the glass substrate by soaking the substrate in a container containing an etchant. In this method, however, the substrate is not etched uniformly because of the non-uniformity of the surface of the substrate. In addition, the impurities generated during the etching process is attached onto the surface of the substrate, so that the surface becomes rough.
To solve the above problem, the substrate is set up in the container containing the etchant and then N2 bubbles are supplied to the surface of the substrate through a porous plate to remove the impurities attached onto the surface of the substrate and apply a new etchant to the surface of the substrate.
FIG. 1 is a top view showing a glass substrate of a conventional liquid crystal display device.
FIG. 1 includes two cells 10, 11 which should be laminated to each other, an exhausting port 13 for exhausting an inner gas, and a guide line 15 for preventing a corrosion of the cells 10, 11 by the etchant from an outer region of the substrate 20. Solid line arrows represent paths for exhausting a gas in the cells 10, 11 to the end region in the glass substrate 20. Dotted line arrows represent paths for exhausting the exhausted gas from the cells 10, 11 to the outer region of the glass substrate 20.
The guide line 15 is formed on the whole area of the substrate 20 to block the cells 10, 11 from an outer region of the substrate 20 except for the exhausting port 13.
In this method, however, in case of a liquid crystal display device having metal elements to be formed on the end surface of the substrate, metal elements are corroded by a partial permeation of the etchant such as HF(hydrofluoric acid) into the inner region of the substrate 20.
Accordingly, the present invention is directed to a glass substrate for liquid crystal display device that substantially obviates one or more of the problems due to limitations and disadvantages of the related art.
An object of the present invention is to provide a glass substrate for liquid crystal display device on which an exhausting port is provided for exhausting an inner gas and for preventing a corrosion of the cells by an etchant from an outer region of the glass substrate.
Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described, a plurality of zig-zag type exhausting ports are formed to exhaust the inner gas in the cells to the outer region of the glass substrate when the cells are laminated to each other. Further, opening regions except for the exhausting port are blocked by the residuum acting as a sealing material being generated when the substrate is etched by the etchant, thereby the metal elements on the array is prevented from the etchant.
The above sealant is printed as a minimum line width on the end surface of the substrate to prevent the permeation of the etchant.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.